A Computational Domain Domain Topology A1 1 steady domain 1 rotating domain Multiple domains Grid coupling technique A2 Sliding Overset Multiple ref. Frames B Propeller Representation Resolution B1 Geometrically resolved Unresolved + Body forces Number of considered blades B2 Complete propeller Single blade + periodicity (matching grids) Single blade + periodicity (non matching grids) C Computational Grid (if both C parts are used: Fied Domain/Part) Type C1 Structured Unstructured Local grid refinement C2 Possible used here Possible not used here Not possible
Primary volume elements C3 Tetraheder Heahedral Polyhedral Primary surface elements C4 Quads Triangles Mied Wall boundary layer type C5 Prism layer He layer Poly layer C6 Blade meshing Homogeneous for all blades One blade refined C7 Number of cells across boundary layer 5 20 5 5 0 4 34 9 20 6 28 Y + value at C8 r/r = 0,4 118 <1 30 30 120 100 0,2 20 1 30 3 0,28 30 ~1 r/r = 0,7 140 <1 30 30 120 150 0,3 30 1 30 3,5 0,42 40 ~1 r/r = 0,9 160 <1 30 30 120 120 0,4 40 1 50 4,2 0,62 50 ~1
C9 Averaged amount of cells per resolved blade 01_BERG 2.762.945 165.000 235.000 235.000 658.000 42.000 12.700 22.000 254.440 90.000 2.500.000 328.380 261.066 26.400 200.000 4.269.568 Averaged amount of nodes per resolved blade C10 65.439 275.680 C Computational Grid (if both C parts are used: Rotating Domain/Part) Type C1 Structured Unstructured Local grid refinement C2 Possible used here Possible not used here Not possible Primary volume elements C3 Tetraheder Heahedral Polyhedral Primary surface elements C4 Quads Traingles Mied
Wall boundary layer type C5 Prism layer He layer Poly layer C6 Blade meshing Homogeneous for all blades One blade refined C7 Number of cells across boundary layer Y + value at C8 r/r = 0,4 22 51 r/r = 0,7 29 32 r/r = 0,9 37 30 Averaged amount of cells per resolved blade C9 1.894.314 2.316.306 C10 Averaged amount of nodes per resolved blade 586.057 2.360.214
D Normalized Dimensions of the Physical Domain (if both D parts are used: Fied domain) D1 for all domains X_min / D 5,58 12 2,28 2,28 3 2 2 2,28 2 0,5 2 2,3 2,3 4 12 5 X_ma / D 13,42 4 8 8 4 3 6 6 4 1 6 5,3 5,3 10 6 10 for non cyl. Domains D2a Y_min / D 4 1,2 1,2 6 Y_ma / D 4 1,2 1,2 6 for non cyl. Domains D3a Z_min / D 4 1,2 1,2 6 Z_ma / D 1,5 1,2 1,2 6 for cyl. Domains 3 3 1,35 3 1,2 0,34 1,34 5 5 5 D2b open water 3 4 cavitation tunnel 1,36 1,35 D Normalized Dimensions of the Physical Domain (if both D parts are used: Rotating domain) for all domains D1 X_min / D 0,7 0,41 X_ma / D 0,6 0,31 for non cyl. Domains D2a Y_min / D Y_ma / D for non cyl. Domains D3a Z_min / D Z_ma / D for cyl. Domains 0,6 0,6 D2b owt. cav
E Numerical Approimation Finite Approimation Scheme (Fluid) Finite volume Navier Stokes E1 Finite element Navier Stokes Mied FV / FE Navier Stokes None Finite Approimation Scheme (Propeller) E2 Navier Stokes BEM VLM Coordinates E3 Cartesian Cylindrical fied Cylindrical rotating Convection scheme (momentum eq.) high order upwind E4 2nd order centered high order centered blended UDS / CDS E5 limited / blended downwind ( compressive) Transient approimation implicit E6 eplicit Special Vorte Treatment Technique: none refinement
E7 E8 E9 E10 01_BERG Spatial order of accuracy (neglecting BC) 2nd order 30 % 1st order; 70 % 2nd order Temporal order of accuracy 1st order 2nd order Time step steady quasi steady 0,5deg / Cycle 3,02E 05 1,00E 04 5,00E 05 Equivalent angle of rot. for a time step 0,25 1 1,00E+00 7,85E10 03 [rad/timestep]
F Turbulence treatment Model name k omega k epsilon one equation model Reynolds stress transport model F1 algebraic stress model hybrid RANS / LES LES SST other (see reference) Inviscid or Laminar Transition F2 Fully turbulent Modelled transition Fied transition Convection scheme (Turbulence Eqn.) 1st order upwind F3 high order upwind 2nd order centered high ordered centered blended UDS / CDS
G Boundary conditions Blade Slip flow (or Euler) G1 Laminar (no slip) Logarithmic Hybrid laminar / logarithmic Hub Slip flow (or Euler) G2 Laminar (no slip) Logarithmic Hybrid laminar / logarithmic G3 Inlet Fied Velocity G4 Fied Pressure Outlet Fied Velocity Fied Pressure Characteristic / Far Field BC Etrapolate / Far Field BC Outer domain Slip flow (or Euler) G5 Laminar (no slip) Logarithmic Hybrid laminar / logarithmic
H Computational Model Fluid H1 compressible incompressible Pressure H2 Equation of state pressure correction / projection scheme Two Phase flow treatment Euler / Euler VOF H3 Euler / Euler VOF (single Phase) Euler / Lagrange Euler / Euler I Cavitation Model Type Mass Transfer VOF Euler / Euler I1 Lagrangian bubble dynamics Thermodynamic equilibrium linear BEM Mass Transfer VOF in addition to Lagrange Author reference I2 Okuda and Ikohagi Merkle Zwart (2004) Initial (minimam) bubble diameter [mm] I3 1,00E 03 1,00E 06 5,00E 03
I4 Maimum bubble diameter [mm] 1,00E+00 Number of bubbles/m³ (nuclei number) I5 1,00E+08 1,00E+12 1,00E+13 Mass transfer / VOF interaction (for VOF) I6 RHS pressure / pc equation RHS and matri of pressure / pc equation I7 Vapor density [kg/m³] 0,02 0,02 0,02 0,03 0,6 0 0,02 Model acronym Kunz k Sauer I8 Zwart z Singhal s Merkle Senocak Condensation source term based on I9 Pressure difference Square root of pressure difference s, z other k Vaporisation source term based on I10 Pressure difference k Square root of pressure difference s, z others
I11 I12 I13 I14 I15 I16 I17 I18 01_BERG Condensation coefficient value 0,01 0,01 25 370 UniTriest Kunz 455 UniTriest Singhal 2,3E 04 s UniTriest Zwart 0,3 Vaporisation coefficient value 0,02 0,02 0,01 370 UniTriest Kunz 4100 UniTriest Singhal 0,4 UniTriest Zwart 300 Limitations to the source term Yes No Limitations to the vapor fraction Yes No Convection scheme 1st order upwind high order upwind 2nd order centered high order centered blended UDS / CDS limited / blended downwind ( compressive) Modification for turbulent flows Yes No Diffusion term employed Yes No Surface tension employed Yes s, z No k
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